Part I. Circle your answers Name: 1. If a sample of matter is uniform throughout and cannot be separated into other substances by physical means, it is. A) a compound B) either a compound or an element C) a homogeneous mixture D) a heterogeneous mixture E) an element 2. What volume of 10.0 M H 2 SO 4 is required to prepare 4.0 L of 0.50 M H 2 SO 4? A) 0.20 L B) 0.40 L C) 0.50 L D) 1.0 L E) 4.0 L 3. A solution of silver nitrate is mixed with a solution of potassium fluoride. If a precipitate forms, the precipitate is: A) Silver fluoride B) Potassium nitrate C) Potassium fluorate D) Nitric fluoride E) No precipitate is formed 4. If 5.0 mol of both hydrochloric acid and sodium sulfide are mixed and reacted according to the equation below, how many moles of hydrogen sulfide (H 2 S) are produced? HCl + Na 2 S à H 2 S + NaCl A) 1 mol B) 1.25 mol C) 2.5 mol D) 3 mol E) 5 mol 5. Which of the following is not a physical process? A) distillation B) filtration C) chromatography D) evaporation E) none of the above
6. Of the choices below, which one is not an ionic compound? A) PCl 5 B) MoCl 6 C) RbCl D) PbCl 2 E) NaCl 7. Boron has two naturally occurring isotopes, 10 B with an atomic mass of 10.0129370 amu and 11 B with an atomic mass of 11.0093054 amu. The atomic mass of boron is 10.81 (from the periodic table). The percent abundances of the boron isotopes are % 10 B and % 11 B. A) 81.0, 19.0 B) 9.9, 90.1 C) 49.0, 51.0 D) 20.0, 80.0 E) 1.0, 99.0 Part II. 8. Complete the following table (all empty cells): NAME FORMULA Calcium chlorate CBr 4 Ammonium phosphate Fe 2 O 3 9. Complete the following table (all empty cells in both rows): Symbol # of protons # of neutrons # of electrons atomic number mass number 51 V +5 18 18 34
10. Selenium, an element used in the manufacture of solar energy devices, forms an oxide that contains only one atom of selenium (per formula unit) and is 37.8% oxygen by mass. What is the molecular formula of the oxide? 11. A solution with a total volume of 1000.0 ml contains 37.1 g Mg(NO 3 ) 2. If you remove 20.0 ml of this solution and then dilute this 20.0 ml sample with water until the new volume equals 500.0 ml, what is the concentration of Mg +2 ion in the 500.0 ml of solution? What is the concentration of nitrate ion? Concentration of Mg +2 Concentration of NO 3 12. For each question below, equal volumes of two aqueous solutions are mixed. List the species that are present (ions, compounds, etc.) and their concentrations after mixing if they remain in solution. Include the phases for the species present. You don t need to list water. a) Equal volumes of a 1.0 M lead (II) nitrate mixed with 1.0 M sodium chloride b) Equal volumes of 1.0 M ammonium carbonate mixed with 1.0 M potassium perchlorate
13. Solid sulfur and oxygen gas react to produce sulfur trioxide as shown below. In a particular experiment, 5.0 g of O 2 are reacted with 6.0 g of S 8. S 8 (s) + O 2 (g) SO 3 (g) a) If we assume complete consumption of the limiting reactant, what is the mass and identity of the reactant that still remains at the end of the reaction? c) What is the % yield of SO 3 in this experiment if 7.9 g of SO 3 are isolated? 14. An iron nail is suspended on a thin wire in a sealed jar of moist air. The surface of the nail becomes red over time. a) Describe what is happening to the mass of the nail over time. b) List the chemical changes taking place in the jar.
2010 IUPAC, the International Union of Pure and Applied Chemistry 1 18 1 H hydrogen 1.008 3 Li lithium 6.941(2) 4 Be beryllium 9.012 atomic number Symbol name standard atomic weight IUPAC Periodic Table of the Elements 2 Key: 13 14 15 16 17 5 B boron 10.81 6 C carbon 12.01 7 N nitrogen 14.01 8 O oxygen 16.00 9 F fluorine 19.00 2 He helium 4.003 10 Ne neon 20.18 11 Na sodium 22.99 12 Mg magnesium 24.31 3 4 5 6 7 8 9 10 11 12 13 Al aluminium 26.98 14 Si silicon 28.09 15 P phosphorus 30.97 16 S sulfur 32.07 17 Cl chlorine 35.45 18 Ar argon 39.95 19 K potassium 39.10 37 Rb rubidium 85.47 55 Cs caesium 132.9 87 Fr francium 20 Ca calcium 40.08 38 Sr strontium 87.61 56 Ba barium 137.3 88 Ra radium 21 Sc scandium 44.96 39 Y yttrium 88.91 57-71 lanthanoids 89-103 actinoids 22 Ti titanium 47.87 40 Zr zirconium 91.22 72 Hf hafnium 178.5 104 Rf rutherfordium 23 V vanadium 50.94 41 Nb niobium 92.91 73 Ta tantalum 180.9 105 Db dubnium 24 Cr chromium 52.00 42 Mo molybdenum 95.96(2) 74 W tungsten 183.9 106 Sg seaborgium 25 Mn manganese 54.94 43 Tc technetium 75 Re rhenium 186.2 107 Bh bohrium 26 Fe iron 55.85 44 Ru ruthenium 101.1 76 Os osmium 190.2 108 Hs hassium 27 Co cobalt 58.93 45 Rh rhodium 102.9 77 Ir iridium 192.2 109 Mt meitnerium 28 Ni nickel 58.69 46 Pd palladium 106.4 78 Pt platinum 195.1 110 Ds darmstadtium 29 Cu copper 63.55 47 Ag silver 107.9 79 Au gold 197.0 111 Rg roentgenium 30 Zn zinc 65.38(2) 48 Cd cadmium 112.4 80 Hg mercury 200.6 112 Cn copernicium 31 Ga gallium 69.72 49 In indium 114.8 81 Tl thallium 204.4 32 Ge germanium 72.64 50 Sn tin 118.7 82 Pb lead 207.2 33 As arsenic 74.92 51 Sb antimony 121.8 83 Bi bismuth 209.0 34 Se selenium 78.96(3) 52 Te tellurium 127.6 84 Po polonium 35 Br bromine 79.90 53 I iodine 126.9 85 At astatine 36 Kr krypton 83.80 54 Xe xenon 131.3 86 Rn radon 57 La lanthanum 138.9 58 Ce cerium 140.1 59 Pr praseodymium 140.9 60 Nd neodymium 144.2 61 Pm promethium 62 Sm samarium 150.4 63 Eu europium 152.0 64 Gd gadolinium 157.3 65 Tb terbium 158.9 66 Dy dysprosium 162.5 67 Ho holmium 164.9 68 Er erbium 167.3 69 Tm thulium 168.9 70 Yb ytterbium 173.1 71 Lu lutetium 175.0 89 Ac actinium 90 Th thorium 232.0 91 Pa protactinium 231.0 92 U uranium 238.0 93 Np neptunium 94 Pu plutonium 95 Am americium 96 Cm curium 97 Bk berkelium 98 Cf californium 99 Es einsteinium 100 Fm fermium 101 Md mendelevium 102 No nobelium 103 Lr lawrencium www.iupac.org/reports/periodic_table This periodic table is dated 19 February 2010 Useful Conversion Factors and Constants 1 mol = 6.022141 10 23 R = 0.082058205 L-atm/mol-K 1 m = 1.0936 yd = 8.314472 J/mol-K 4.184 kj = 1 kcal = 3.1415927 1 in = 2.54 cm (exact) c = 2.99792458 10 8 m/s